Assess sediment dynamics and contamination levels in the wetlands of Lake Saint-Pierre

Context and project description

How do we know the degree to which municipal and industrial wastewater, agricultural contaminants, ice jams and river dredging have historically had, and continue to have, an impact on the wetlands of Lake Saint-Pierre? By taking cores from the sediment beds of these habitats to measure certain indicators, such as the levels of sedimentation and contamination. This is what the project’s participants will do in the lake’s six major wetlands, which also correspond to some of the largest wetlands on the St. Lawrence.

Essential to the reproduction and sustenance of a multitude of animal species, these habitats are continually subject to the sedimentation process. The project’s objective is to measure this sedimentary dynamic. We will be assessing the sedimentation rate and the age of sediments, calculating their concentration of organic carbon, nitrogen and phosphorus, and metering their concentration of contaminants of industrial and urban origin (metals, mercury, PAH, PCB, PBDE etc.).


A number of sediment samples were collected and analyzed in the laboratory for indicators such as the organic carbon, nitrogen and phosphorus concentrations, as well as the sediment deposition rate. The results of the analysis of these indicators will be presented in a scientific fact sheet. Overall, the project has helped increase knowledge of the sedimentology of the wetlands in Lake Saint-Pierre and of the potential impact of human activities and natural environmental variables on these critical wetlands.

Participating departments

The Government of Canada

  • Environment and Climate Change Canada

Government of Quebec

  • Ministère des Forêts, de la Faune et des Parcs
  • Ministère du Développement durable, de l’Environnement et de la Lutte contre les changements climatiques